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The Alchemist takes his beverages caffeine free this week to avoid confusion but is intrigued to learn that antibiotics almost three-fourths of a century old have finally yielded the mode of action. In the world of materials, we have shape-shifting polymers and nanotrees split water in sunlight. There is now a way to brew microbes fed on straw to ferment lipid residues from a corn fungus to make "green" ingredients for detergents. Finally, the 2011 Tetrahedron Prize will be awarded to Manfred Reetz later this year.




Researchers in Germany have developed an informatics approach to determining whether a beverage or food product contains natural or synthetic caffeine. The technique could allow regulators to check how well manufacturers of added-caffeine products are adhering to the rules regarding caffeine source in their product labeling and marketing campaigns. The team found that several well-known products available on supermarket shelves and labeled "natural" actually contained quantities of synthetic caffeine. The team suggests that their approach has the potential to become a routine method for authenticity control of caffeine-containing products.





X-ray crystallography has revealed the mode of action of so-called sulfa antibiotics, which have been used in medicine for more than 70 years but which suffer from several side effects as well as bacterial resistance. The research, carried out by researchers from St Jude Children's Hospital, reveals in atomic detail the mode of action of these drugs by focusing closely on the enzyme dihydropteroate synthase. The work could point the way to a new generation of antibiotics with fewer side effects that also potentially side step the issue of resistance.





A new range of photoresponsive polymers can adopt different three-dimensional shapes when exposed to light through a pair of patterned photo masks, according to Ryan Hayward and colleagues at the University of Massachusetts, Amherst, US. In much the same way that a flat leaf can curl to form 3D shapes, so the layered polymers can be made to form caps, almost spherical structures and more complex surfaces by appropriate patterning and exposure to light. The process happens reversibly and might be useful in mimicking the behavior and structure of human tissues for artificial muscles and self-actuated systems or even in tissue engineering acting as dynamic scaffolds on which new organs might be grown.





Nanoscopic "trees" can harvest sunlight and use it to convert water into hydrogen fuel, according to research from the University of California, San Diego. Deli Wang and colleagues have created a branched nanoarray from silicon/zinc oxide nanowires to produce an enormous surface area for energy harvesting. Photons bounce between the branches of the 3D branched nanowire heterojunction photoelectrodes and so increase water photolysis and so release hydrogen more efficiently than planar materials. The next step is to find a more stable alternative to zinc oxide.





Researchers in Germany have found an alternative to oil-derived surfactants based on microbial fermentation of cellobiose lipids (CL) and mannosylerythritol lipids (MEL). These materials could be sustainably sourced and so offer manufacturers of cleaning products a so-called "green" alternative. Suzanne Zibek of the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB and colleagues point out that these lipids are produced in large quantities by smut fungi that infect corn plants. The surfactants brewed up from these compounds are biodegradable, less toxic than petroleum-based products and are just as effective as conventional cleaning agents at emulsifying fats. The team adds that sugar extracted from straw can even be used as the food source for the fermentation process.





Elsevier, the Publisher of Tetrahedron Publications, will present the 2011 Tetrahedron Prize for Creativity in Organic Chemistry to Manfred Reetz of the Max-Planck-Institut fur Kohlenforschung, Germany, at the 2012 Fall meeting of the American Chemical Society. Reetz has made numerous contributions to synthetic organic chemistry with a particular focus on enantioselective catalysis for the control of stereoselectivity using transition-metal catalysts. He has recently been prominent in the development of catalysts for asymmetric reactions.